Machine eoe



G. W. HOLMAN. Grinding Mill.

No. 22.806. Patented Feb.` i, i859.

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GEORGE XV HOLMAN,

OF BELIT,` VISCONSIN.

Specification of Letters Patent No.

To all whom it may concern.'

Be it known that I, GEORGE WV. HOLMAN, of the city of Beloit and county of Rock, in the State of lVisconsin, have invented a new and useful Improvement on Machines for Making Meal and Flour; and l do hereby decla-re that the following is a full, clear, and exact description of the construction and operation of the machine thus improved, reference being had to the annexed drawings, making a part of this specification, in which- Figure Nofl is an isometrical drawing, Fig. 2 a transverse section; Fig. 3 a transverse section of the core, in the middle; Fig. et a transverse section of the core, at the end; Fig. 5 a side view of one of the knives; F ig. 6 a plan of the band by which the knives are vadjusted with the tangent screw, moving the same; Fig. 7 an isometrical drawing of a wheel, composed of lead and emery, or of stone, to be used in sharpening the knives.

The heads b are held in position by the posts c o. The knives e a are supported by gudgeons Z Z resting in sockets in the heads Z), Z2. The band f passes around at one end of the knives, outside of the gudgeons CZ l lying in a depression in the head Z2.

The pivots e fit into the slots g g of the band f. The knives are thus all connected together by the band. The band is moved by the tangent screw 7L. By moving the band, the knives are all turned upon their gudgeons. In Fig. 5, t is the face of the knife, which is slightly concave, o is the front or cut-ting edge of the face, and w the back edge of the face. By moving the band in one direction the front edges of the faces of the knives are thrown in toward the axis of the arbor z' and the back edges of the faces out from the axis, by which motion apertures are formed between the several knives, all of equal dimensions; the back edge of the face of one knife gaging the thickness of the shaving cut by the front edge of the face of the one next tol it.

By moving the band in the opposite direction these apertures are closed, and the faces unite to form a smooth concave surface. This surface differs from the interior surface of a hollow cylinder by being made somewhatsmaller at the head b than at the head b, for convenience in sharpening the knives, as will be explained hereafter.

22,806, dated February 1, 1859.

The core (Figs. 3 and t) is attached to the arbor e' and projects about of an inc h outside of the heads b o. The threads 7a 7e of the core diminish from each end, to the center of the core, as shown in the drawings and each thread passes one third around the core, in passing from the end to the center.

The machine is set in motion by a band passing around the pulley Z, which is attached to the arbor 2f. Motion is communicated from the arbor z' to the arbor n by a band connecting the cone pulleys m and m. The grain is placed in the hopper 0, and being drawn each way by the threads Q0 j) of the arbor n, drops through apertures in the blocks g and r upon the ends of the core (Fig. 4). Thence the threads la draw it toward the center and press it against the edges of the knives which cut it (fine or coarse, according to the openings between them, given by the tangent screw la) and allows it to pass out between them, whence it falls upon, and slides down the apron s.

The knives a a are of cast steel. The apron s, is of sheet iron. `The tangent screw L is of wroughtiron. The hopper 0 is of wood. Theband connecting the cone pulleys m and m, is of leather. All other parts of the machine are formed of cast iron.

Fig. 7 is a wheel composed of lead and emery, or of stone. It is somewhat smaller at one end than at the other, as is the space which is surrounded by the faces of the knives a a. To grind the knives the block 1" and the cone pulley m, are removed from the head of the machine, the core is drawn off from the arbor z' and the emery wheel is put onin its place, a slot in the wheel slipping over a stay pin on the arbor. The block r is then replaced and the wheel is pressed into close contact with the knives by turning up the thumb screw w. As the knives are worn away, the conical eme-.ry wheel is pressed farther in, by the thumb screw a', till they are sufficiently sharpened. I also contemplate the application of knives uniformly adjustable, in a manner substantially the same as that set forth, to the cutting of wood. l

I do not claim adjustable knives for the purpose of grinding grain, or screws for feeding grain to grinding surfaces in mill, or cone pulleys, or tangent screws, or emery wheel for sharpening knives: but

I do claim- 1. The placing a series of knives, supported by gudgeons, in a circle, or part of a circle7 so that the thickness of the shaving cut by the edge of one knife shall be gaged by the back of the knife next to it, as and for the purpose specified.

2. And I also claim the placing a series of knives supported by gudgeons so that the rankness of set of all them may be uniformly graduated by one operation, and so that their faces may be thrown back into one uniform surface for grinding or sharpening, substantially as set forth.

E. F. HOBART, CHAS. A. WILBUR. 

